Fiber-optic interconnection stabilization apparatus

ABSTRACT

A fiber-optic interconnection stabilization apparatus for a measurement system is provided. The apparatus may comprise a main body comprising an enclosure and two openings. The enclosure may encase a fiber-optic cable within the main body in an organized manner. The two openings may fit connecting ends of the fiber-optic cable such that the connecting ends of may be exposed in order to connect two modular components of a measurement system and form a closed measurement loop. The main body, when in a closed configuration, may stabilizes the fiber-optic cable encased within from external conditions, such as mechanical, thermal, or other environmental conditions that may affect measurements.

PRIORITY

The present application is a Continuation of commonly assigned and U.S.patent application Ser. No. 15/996,136, filed Jun. 1, 2018, now U.S.Pat. No. 10,928,274 B2, which claims priority to U.S. Provisional PatentApplication No. 62/641,173, entitled “Fiber-Optic InterconnectionStabilization Apparatus,” filed on Mar. 9, 2018, which are incorporatedby reference in their entirety.

BACKGROUND

Some network testing devices, especially those that measure and testinsertion loss (IL), optical return loss (ORL), polarization dependentloss (PDL), and extinction ratio (ER), may be provided in single-boxmeasurement platform. This network testing device will typically bepreconfigured to include various modular testing components orcassettes. These may include a single output light source, standardconnector adapters, one or more measurement elements, etc., within asingle-bodied chassis. As a single testing unit, the network testingdevice may be able to handle most, if not all, measurement and testingdeterminations. For external sources not included in the network testingdevice, a fiber-optic cable (or jumper) may be used to connect theexternal source, or other modular system components to the networktesting device.

In order to provide an interconnection between two modular testingcomponents in the network testing device, a fiber-optic interconnect,for example, may be required to close a testing or measurement loop.However, a technical problem associated with such a configuration isthat the fiber-topic interconnect is often exposed. This means theoptical fiber may be affected by environmental elements, which in turnmay lead to inaccurate measurements and readings by the network testingdevice. As a result, a fiber-optic interconnection stabilizationapparatus may be needed.

BRIEF DESCRIPTION OF DRAWINGS

Features of the present disclosure are illustrated by way of example andnot limited in the following Figure(s), in which like numerals indicatelike elements, in which:

FIG. 1 illustrates a measurement system using a fiber-opticinterconnect, according to an example;

FIG. 2 illustrates a measurement system using a fiber-optic interconnectstabilization apparatus, according to an example;

FIG. 3 illustrates a cross-section of a measurement system using afiber-optic interconnect stabilization apparatus, according to anexample;

FIGS. 4A-4E illustrate various views of a fiber-optic interconnectionstabilization apparatus, according to an example; and

FIGS. 5A-5C illustrate various views of a fiber-optic interconnectionstabilization apparatus, according to another example.

DETAILED DESCRIPTION

For simplicity and illustrative purposes, the present disclosure isdescribed by referring mainly to examples and embodiments thereof. Inthe following description, numerous specific details are set forth inorder to provide a thorough understanding of the present disclosure. Itwill be readily apparent, however, that the present disclosure may bepracticed without limitation to these specific details. In otherinstances, some methods and structures readily understood by one ofordinary skill in the art have not been described in detail so as not tounnecessarily obscure the present disclosure. As used herein, the terms“a” and “an” are intended to denote at least one of a particularelement, the term “includes” means includes but not limited to, the term“including” means including but not limited to, and the term “based on”means based at least in part on.

Measuring and comparing optical return loss (ORL) in a network hasbecome increasingly important in network provisioning and maintenance.There are two general techniques for measuring optical return loss(ORL): (1) time-domain measurements, and (2) optical-continuous-wavereflectometry (OCWR). Despite differences in sensitivity between thesetechniques and how equivalent measurements are obtained, both techniquesmay be widely used for measuring ORL. The newer time-domain techniques,however, have recently become more popular because of their ease of use,speed, and dynamic range and capabilities.

Optical loss return (ORL) is the ratio between the light launched into adevice and the light reflected by a defined length or region. For ORLmeasurements, regardless of method (e.g., time-domain reflectometry(TDR), optical-continuous-wave reflectometry (OCWR), or othertechnique), length is an important factor and it may be defineddifferently for each type of measurement technique. Reflections andscattering of light within fiber may affect data transmission andperformance. Therefore, ensuring fiber-optic integrity of aninterconnect, for example, may be essential to more accurate andreliable network testing and measurements.

As described above, current measurement devices that measure and testinsertion loss (IL), optical return loss (ORL), polarization dependentloss (PDL), extinction ratio (ER), and/or other optical signals in anetwork may be provided in single-box measurement system. As a result,these network devices that contain a plurality of modular components orcassettes may often need a fiber-optic interconnect to close ameasurement loop in order to perform a measurement or otherdetermination. Because such a fiber-optic interconnect may be asingle-mode (SM) optical fiber that is exposed to various environmentalconditions. These conditions may be mechanical (e.g., twisting, pulling,turning, kinking, etc.) or thermal, or may be based on proximity toother forms of interference. As a result of these external perturbationsor fluctuations, measurements by the network testing device may not beas accurate or reliable as they could be with a more stabilizedfiber-optic interconnect. Accordingly, a fiber-optic interconnectionstabilization apparatus is described herein.

FIG. 1 illustrates a measurement system 100 using a fiber-opticinterconnect, according to an example. In an example, the measurementsystem 100 may be an ORL measurement system. Although examples describedherein are generally directed to an ORL measurement system, it should beappreciated that the ORL measurement system 100 may also be used formeasuring insertion loss (IL), optical return loss (ORL), polarizationdependent loss (PDL), extinction ratio (ER), and/or run other opticalsignals or measurements. As depicted, the ORL measurement system 100 maybe a single-box platform. In an example, the ORL measurement system 100may include a chassis 102 containing a display 104 for a unifiedapplication. In an example, the ORL measurement system 100 may include aplurality of modular components. These modular components may beprovided in cassette form (or other suitable form), which may beinserted into the chassis 102. In an example, the ORL measurement system100 may include Cassette 1 106 a and Cassette 2 106 b. It should beappreciated that while only two cassettes 106 a and 106 b or modularcomponents are shown, there may be more or less depending on chassissize or other predetermined configurations. In FIG. 1 , Cassette 1 106 amay be a single output light source (e.g., MSRC, MTLG, etc.), andCassette 2 106 b may be a measurement module family (e.g., single mode(SM): IL/RL (return loss), multimode (MM): IL/RL, etc.). Other variousconfigurations may also be provided.

Cassette 1 106 a and Cassette 2 106 b, in this example, may include avariety of input/output ports and/or adapters. These may be forconnecting power, cables, wires, or other inputs/outputs. In someexamples, the ORL measurement system 100 may have at least an Ethernetconnection to connect to other computing devices 108, such as areporting tool or other system. Other various ports, adapters,connections may also be provided. Also as shown in FIG. 1 , Cassette 2106 b may include ports or adapter to a fiber-optic cable (or jumper),which may be used to connect the ORL measurement system 100 to anexternal source. In an example, this external source may be a deviceunder test (DUT) 110 or other network component in which measurementsare to be measured and taken.

As shown in FIG. 1 , Cassette 1 and Cassette 2 may be connected by afiber-optic interconnect 112, which may be another fiber-optic cable.The fiber-optic interconnect 112 may be exposed to external conditions.These conditions may cause fluctuations and perturbations that may bemechanical, thermal, or other environment condition that may adverselyaffect potential measurements by the ORL measurement system 100. Asdescribed above, it may be important for an optical signal to be asstable as possible, especially for ORL measurements that involveparameters of IL and polarization stability. Therefore, as shown in FIG.1 , the fiber-optic interconnect 112 may be encased in a fiber-opticinterconnect stabilization apparatus 200, which will be described ingreater detail below.

In some examples, the interconnect 112 may be a polarization-maintaining(PM) optical fiber. A PM fiber may be a single-mode optical fiber inwhich linearly polarized light maintains a linear polarization duringpropagation. In other words, a PM fiber may allow light to exit withlittle or no cross-coupling of optical power between two polarizationmodes. A PM fiber may work to stabilize polarization fluctuations andmay be helpful to preserve polarization where that is important. In somesituations, a PM fiber may provide adequate stabilization since somesources in the modular components may not be properly aligned topolarization axes of a fiber.

In some examples, the interconnect 112 may be a single-mode (SM) opticalfiber. An SM fiber may be more sensitive to polarization fluctuations,and in certain cases where use of PM fiber is precluded, steps may betaken to minimize polarization fluctuations. Since an SM fiber may bemore affected by external factors, stabilization may help minimizepolarization issues. In other examples, such as a vibrating ormechanically noisy environment, a fiber resting on a bench, forinstance, may be more easily jostled or disturbed. In this scenario, thefiber may be encapsulated and to remove it from direct contact with thebench, ultimately isolating it from mechanical disturbances.

FIG. 2 illustrates a measurement system 100 using a fiber-opticinterconnect stabilization apparatus 200, according to an example. An SMfiber may be used as the fiber-optic interconnect for the modularcomponents of the ORL measurement system 100. A fiber-opticinterconnection stabilization apparatus 200 may be used to encase thefiber-optic interconnect and reduce at least some adverse externalconditions and influences, while maintaining its core function ofconnecting two intermodular measurement components or cassettes (e.g.,106 a and 106 b).

FIG. 3 illustrates a cross-section of a measurement system 100 using afiber-optic interconnection stabilization apparatus 200, according to anexample. As shown in FIG. 3 , a fiber-optic interconnectionstabilization apparatus 200 may be used to effectively form a “rigidjumper” to form a closed measurement loop. The rigid jumper may be thefiber-optic interconnect stabilization apparatus that encases thefiber-optic interconnect cable that connects Cassette 1 106 a andCassette 2 106 b. It should be appreciated that a DUT 110 (e.g., SMPCT/MORL) may be connected to the ORL measurement system 100 by otherfiber-optic cables or jumpers, as shown. It should be appreciated thatFIG. 3 may provide one exemplary configuration. Other variousconfigurations and uses of the fiber-optic interconnection stabilizationapparatus 200 and/or the DUT 110 may also be provided and are notintended to be limited by what is shown in FIG. 3 .

FIGS. 4A-4E illustrate various views of a fiber-optic interconnectionstabilization apparatus 200, according to an example. FIG. 4A depicts anisometric view of a fiber-optic interconnection stabilization apparatus.FIG. 4B depicts a side view of a fiber-optic interconnectionstabilization apparatus. In the side view, the fiber-opticinterconnection stabilization apparatus may have a particular thicknessor height (H) (e.g., 10 mm). As shown, the fiber-optic interconnectionstabilization apparatus may have a main body 402 with an enclosure tocontain a fiber-optic interconnect 112 in an organized way. Thefiber-optic interconnection stabilization apparatus 200 may have an openconfiguration and a closed configuration. In order to have two suchconfigurations, the fiber-optic interconnection stabilization apparatus200 may have the capability to be opened and closed via mechanical,magnetic, electrical, or other feature. In an example, the main body mayhave two mating portions, e.g., a top portion 404 and a bottom portion406. The top portion 404 and bottom portion 406 may be mechanicallyattached to enclose the fiber-optic interconnect 112. In one example,the top portion 404 and the bottom portion 406 of the main body 402 maybe fully separated. In another example, the top portion 404 and thebottom portion 406 of the main body 402 may be attached at a joint (notshown). For example, there may be a hinge and a latch which may be usedto open and close the main body 402, such as a clamshell design. Inother examples, the top portion 404 and the bottom portion 406 of themain body 402 may be attached using epoxy or other similar materials.Other various configurations may also be provided.

In some examples, the main body 402 of the fiber-optic interconnectionstabilization apparatus 200 may also include two openings 408. Theseopenings may be configured to allow connecting ends 410 of thefiber-optic interconnect 112 to be fitted in the main body 402, suchthat when the fiber-optic interconnection stabilization apparatus 200 isin a closed configuration, the entire fiber-optic interconnectionstabilization apparatus 200, together with the optical-fiberinterconnect fitted within, becomes a rigid jumper rather than just aloosely dangling optical cable.

FIG. 4C depicts a top cross-section view of a fiber-opticinterconnection stabilization apparatus 200. In this example, thefiber-optic interconnection stabilization apparatus 200 may be shown tohave an SM fiber coiled in the enclosure of the main body 402. In oneexample, the interior of the main body may have a molded area 412 in theshape of a cylinder around which the fiber may be coiled. Other variousdesigns may be provided to ensure organization or stabilization of thefiber within the main body 402. As shown, the fiber-opticinterconnection stabilization apparatus 200 may have two openings 408fitted to receive connecting ends 410 of a fiber-optic interconnect,such as an SM fiber. It should be appreciated that each opening 408 mayhave an axial gap 414 that is designed to fit each connecting end 410 ofthe fiber-optic interconnect 112 to help retain the connecting ends ofthe fiber and ensure stabilization of the fiber.

It should be appreciated that in the event the connecting end 210 doesnot fit exactly within the opening 408, various fittings or materialsmay be provided. For example, if a connecting end 410 is too small forthe opening 408, an attachment 416 may be provided to ensure a stablefit. It should be appreciated that attachment 416 may come in a varietyof sizes, shapes, and/or materials. In another example, if there is toomuch space in the enclosure 411 which allows the fiber 112 to moveexcessively, a padding (not shown) material may be inserted in theenclosure 411 to provide a more secure fit. Again, the padding may comein a variety of sizes, shapes, and/or materials. These and other variousstabilization options may also be provided to ensure the fiber 112 issecurely fitted within the main body 402 of the fiber-opticinterconnection stabilization apparatus 200.

FIG. 4D depicts a top view of a fiber-optic interconnectionstabilization apparatus 200 having exemplary dimensions. As shown, thefiber-optic interconnection stabilization apparatus 200, together withthe encased fiber, may have a length (L) of 71.5 mm and a width (VV) of55.0 mm, such that the connecting ends 410 of the protruding fiber-opticinterconnect 112 may be 41.0 mm apart (X), which may be what is neededto close the measurement loop of the ORL measurement system. Whilespecific dimensions are shown, it should be appreciated that otherdimensions, lengths, and sizes may be provided depending on other needsof the measurement system or other implementations of the apparatus.Furthermore, it should be appreciated that while examples describedherein are directed to depictions of two ports being used to connect twocassettes, other various may be provided as well. For instance, afiber-optic interconnection stabilization apparatus 200 may be used inconfigurations with more than two ports interconnecting more than twocassettes as well.

FIG. 4E depicts a cross-section view A-A of the fiber-opticinterconnection stabilization apparatus 200 shown in FIG. 4D. In FIG.4E, the fiber-optic interconnection stabilization apparatus 200 mayinclude a translation gap 416, a rotation gap 418, a u-shape bracket 420to control rotation and/or translation. It should be appreciated thatthese configurations and designs may allow compatibility to differenttypes of interconnects or connecting ends, as well as offer someflexibility of movement for the fiber-optic interconnectionstabilization apparatus in the event the connecting ends of the fibermay not always line up with the ports of Cassette 1 and Cassette 2.

It should be appreciated that the fiber-optic interconnectionstabilization apparatus 200, as described herein, may be made of variousmaterials. In an example, the fiber-optic interconnection stabilizationapparatus 200 may be made of metal (e.g., aluminum, etc.). A metallicmaterial may allow a thermal mass associated with it. This maystabilize, integrate, and otherwise lessen thermal fluctuations asnormally felt by an enclosed fiber. It should be appreciated that othermaterials for the fiber-optic interconnection stabilization apparatus200 may also be provided, such as rubber, plastic, glass, carbon fiber,or other composites. Whatever materials are used, it should beappreciated that the fiber-optic interconnection stabilization apparatus200 has some mechanical rigidity. As described herein, rigidity may helpprovide stability against polarization fluctuations caused by movementfor non-PM fibers.

It should be appreciated that other configurations for a fiber-opticinterconnection stabilization apparatus 200 may be provided. FIGS. 5A-5Cillustrate various views of a fiber-optic interconnection stabilizationapparatus 200, according to another example. In this case, thefiber-optic interconnection stabilization apparatus 200 may include afloating connector design. For example, the connecting ends may befitted within the opening of the fiber-optic interconnectionstabilization apparatus yet have some space or freedom to move sideways.Such movement may or may not include angular movement. In some examples,use of viscoelastic plastic, or other material, may be used to smoothout such spacing and minimize freedom of movement.

In some examples, a specific clocking angle may be provided for thefiber-optic interconnection stabilization apparatus on the connector.Alternatively or additionally, some ability to adapt the spacing forinter-cassette positional and angular tolerances may also be provided.These configurations may balance rigidity with flexibility (e.g., strictsagittal angular tol on the connector keying, but allow some flexibilityin lateral displacement and azimuthal/elevation angles) that ultimatelyresults in a fiber-optic interconnection stabilization apparatus 200that may be more universally used for inter-cassette connections (orother connections) in various types of ORL measurement systems.

Ultimately, a fiber-optic interconnection stabilization apparatus 200 asdescribed herein may stabilize a fiber-optic interconnect cable frommechanical, thermal, or other environmental stresses that affect ORLmeasurements. Thus, the fiber-optic interconnection stabilizationapparatus 200 maximizes stability and provides improved IL/PDL/RLmeasurements by an ORL measurement system 100.

What has been described and illustrated herein are examples of thedisclosure along with some variations. The terms, descriptions, andfigures used herein are set forth by way of illustration only and arenot meant as limitations. Many variations are possible within the scopeof the disclosure, which is intended to be defined by the followingclaims—and their equivalents—in which all terms are meant in theirbroadest reasonable sense unless otherwise indicated.

The invention claimed is:
 1. A method of using a fiber-opticinterconnection stabilization apparatus in a measurement system, themethod comprising: providing a main body comprising an enclosure and twoopenings, wherein the main body is in an open configuration or a closedconfiguration; encasing a fiber-optic cable within the enclosure of themain body in an organized manner, the fiber-optic cable having twoconnecting ends; fitting each of the two connecting ends of thefiber-optic cable to one of the two openings of the main body, whereinthe two openings of the main body are separated by a predetermineddistance such that the two connecting ends of the fiber-optic cable areseparated by the predetermined distance and are exposed to provideinterconnectivity between two adjacent modular components of themeasurement system and form a closed measurement loop, and wherein thepredetermined distance between the two openings of the main body matchesa distance between ports of the two adjacent modular components; andproviding stabilization to the fiber-optic cable inside the enclosurefrom external conditions when the main body is in the closedconfiguration.
 2. The method of claim 1, wherein the main body comprisesa top portion attached to a bottom portion to form the closedconfiguration of the main body.
 3. The method of claim 1, wherein themain body has a clamshell design.
 4. The method of claim 1, wherein aninterior of the enclosure comprises a molded area around which thefiber-optic cable is organized.
 5. The method of claim 4, wherein themolded area has a cylindrical shape around which the fiber-optic cableis to be coiled.
 6. The method of claim 1, wherein the main body isformed of material that is at least one of metallic, rubber, plastic,carbon fiber, glass, and moldable material.
 7. The method of claim 1,wherein the external conditions are at least one of mechanical, thermal,and environmental.
 8. The method of claim 1, wherein each of the twoopenings comprises at least one of a translation gap, a rotation gap, anaxial gap, and a u-shaped bracket to provide compatibility to differenttypes of connecting ends and flexibility of movement within for thefiber-optic interconnection stabilization apparatus.
 9. The method ofclaim 1, wherein the measurement system measures at least one ofinsertion loss (IL), optical return loss (ORL), polarization dependentloss (PDL), and extinction ratio (ER).
 10. A method of making afiber-optic interconnection stabilization apparatus in a measurementsystem, the method comprising: providing a main body comprising anenclosure and two openings, wherein the enclosure of the main bodycomprises a top portion and a bottom portion, the top portion attachedto the bottom portion to form a closed configuration of the main body,wherein: the enclosure to encase a fiber-optic cable within the mainbody in an organized manner, the fiber-optic cable having two connectingends; and each of the two openings of the main body to fit one of thetwo connecting ends of the fiber-optic cable from within the main body,wherein the two openings of the main body are separated by apredetermined distance such that the two connecting ends of thefiber-optic cable are separated by the predetermined distance and areexposed to provide interconnectivity between two adjacent modularcomponents of the measurement system and a closed measurement loop, andwherein the predetermined distance between the two openings of the mainbody matches a distance between ports of the two adjacent modularcomponents; and wherein the main body, when in the closed configuration,stabilizes the fiber-optic cable from external conditions.
 11. Themethod of claim 10, wherein the main body is formed of material that isat least one of metallic, rubber, plastic, carbon fiber, glass, andmoldable material, and wherein the enclosure comprises a molded area ina cylindrical shape around which the fiber-optic cable is coiled andorganized.
 12. The method of claim 10, wherein each of the two openingscomprises at least one of a translation gap, a rotation gap, an axialgap, and a u-shaped bracket to provide compatibility to different typesof the two connecting ends of the fiber-optic cable and flexibility ofmovement within for the fiber-optic interconnection stabilizationapparatus.
 13. The method of claim 10, wherein the measurement systemmeasures at least one of insertion loss (IL), optical return loss (ORL),polarization dependent loss (PDL), and extinction ratio (ER).